How to Make It
Preheat the oven to 300°. Combine the fennel, coriander and cumin seeds in a spice grinder and grind to a powder. Transfer to a small bowl and stir in the rosemary. Season the lamb chops with salt and coat with the spice mixture; refrigerate for 1 hour.
In a shallow glass or ceramic baking dish, toss the cherry tomatoes with 1/4 cup of the olive oil and the garlic, bay leaves, thyme sprigs, vinegar and shallot. Add a pinch of salt and bake for about 30 minutes, until the tomatoes are soft.
Meanwhile, bring a medium saucepan of salted water to a boil. Add the peas and cook until just tender, about 3 minutes. With a slotted spoon, transfer the peas to a bowl. Add the fava beans to the pan and cook until bright green, about 1 minute. Drain the favas and squeeze each one lightly to pop the bean from its skin. Add the favas to the peas.
In a large skillet, heat the remaining 2 tablespoons of olive oil until shimmering. Add the chanterelles, season with salt and cook over moderately high heat until softened, 3 minutes. Reduce the heat to moderate and cook, stirring occasionally, until the chanterelles are tender and browned, about 5 minutes longer. Add 1 tablespoon of the butter and the pearl onions, cut side down, and cook over moderate heat until golden on the bottom, 3 minutes. Add the chicken stock and simmer over moderate heat until the pearl onions are tender, about 3 minutes longer. Stir the peas and fava beans into the skillet.
Light a grill. Discard the bay leaves and thyme sprigs. Add the tomato mixture to the vegetable ragout and simmer for 3 minutes. Remove from the heat and stir in the mint, tarragon and marjoram. Add the remaining 2 tablespoons of butter, 1 tablespoon at a time, stirring until melted. Season the ragout with salt and pepper.
Grill the lamb chops over high heat until nicely charred on the outside and medium-rare within, about 3 minutes per side. Spoon the ragout into 4 shallow bowls, top with the lamb chops and serve.